Nobita's Undersea Fortress

Doraemon: Nobita and the Castle of the Undersea Devil is a 1983 Japanese animated science fantasy film and the fourth Doraemon feature film, released on March 12, 1983, in Japan. Being the first film in the series to be directed by Tsutomu Shibayama, the film is loosely based on the Western myth of Atlantis, the mythical continent of Mu and the 1980 chapter "8 Days at the Dragon King's Palace".